1. Field of the Invention
The present invention relates generally to a method of controlling an automatic guided vehicle system, and more particularly, to a method of controlling an automatic guided vehicle system having a plurality of automatic guided vehicles, which is capable of efficiently managing the automatic guided vehicles.
2. Description of the Related Art
In general, an Automatic Guided Vehicle (AGV) system is used to automate loading and conveying of articles, and employs an AGV. The AGV is an apparatus used to move loaded articles along a guideline located on a ground. A continuous guideline made of a magnetic tape is installed on a moving path of the AGV, and the AGV detects the guideline via a magnetic sensor, so the AGV travels along the continuous guideline.
FIG. 1A is a schematic diagram illustrating an operation of a conventional AGV system. Referring to FIG. 1A, in a conventional AGV system, a single AGV 20 performs tasks J1, J2 and J3 on a moving path 10 along which the tasks J1, J2 and J3 exist. The AGV 20 receives task commands transmitted from a main control unit 30, and then performs the tasks while traveling along the moving path 10. The AGV 20 performs the tasks according to an order of reception of the task commands.
FIG. 1B is a flowchart illustrating a conventional method of controlling the conventional AGV system. Referring to FIG. 1B, the AGV 20 initializes data at operation S10. If the initialization of the data is completed, the AGV 20 receives the task commands from the main control unit 30, and sets an order of the tasks to be performed according to the task commands at operation S20. The AGV 20 sets the order of the tasks to correspond to the order of reception of the task commands transmitted from the main control unit 30 in accordance with a First-In First-Out (FIFO) rule. According to the FIFO rule, a task command which is input first, is the task command which will be output and performed first by the AGV 20.
Thereafter, it is determined whether preparation of the AGV 20 to perform the tasks has been completed at operation S30. If the preparation of the AGV 20 to perform the tasks has been completed, the AGV 20 performs the tasks while traveling along the moving path 10 according to the order of tasks set at operation S20, at operation S40. The AGV 20 first performs a task corresponding to a first received task command in accordance with the FIFO rule as described above. Thereafter, it is determined whether a current task has been completed at operation S50. As a result, if the current task has been completed, it is determined whether all the tasks corresponding to the received task commands have been completed at operation S60. If all the tasks have been completed, a process of the operation of the conventional AGV system is terminated.
As described above, the conventional AGV system has a single AGV and performs the first received task command according to the FIFO rule. That is, when the conventional AGV system is operated to perform task J1, task J2, and task J3, the AGV 20 first performs the task J1, passes the task J2, moves to a location of the task J3 and secondly performs the task J3. Thereafter, the AGV 20 performs the task J2 after moving to a location of the task J2.
Accordingly, since the conventional AGV system uses the single AGV and first performs a first received task without a moving distance being taken into consideration, the moving distance of the single AGV becomes unnecessarily long and causes much time to be consumed to perform tasks, thereby deteriorating efficiency of completing the tasks and productivity of the operation of the AGV system.